In the manufacture of firearms, and in particular long guns including rifles and shotguns, the production of gun barrels has been performed by a variety of different methods, all of which generally produce a continuous tube. Typically, the tube is formed from a high strength material, such as alloy steel, so as to be capable of withstanding the extreme internal pressures generated during the discharge of a round of ammunition. For example, with the discharge of a shotgun shell, internal chamber pressures in excess of 10,000-15,000 psi can be generated in the chamber and breech sections of the firearm. Firearm barrels typically consist of a chamber or breech region in which the round of ammunition or shell is inserted, and a barrel tube defining the bore of the barrel. Shotgun barrels further typically include a choke section along the barrel, in which a removable choke tube can be received. Externally, the size and length of the barrel tube can vary depending upon the type of firearm, but usually is tapered from the breech or chamber region toward the muzzle end of the barrel in an effort to optimize barrel thickness and weight based on bore pressure variations/reductions as the shot progresses away from the chamber region.
Due to the significant taper or reduction in wall thickness of most typical gun barrels, and in particular shotgun barrels, it is generally not cost effective to machine or cut-down a solid bar or tube having a uniform cross-section to provide the desired taper and reduce the weight of the barrel. Consequently, most firearm barrels typically are hammer forged from shorter blanks to form tapered walled tubes between 20-34 inches in length. Although more cost effective than machining, such forging operations still typically require significant effort and processing to try to ensure straightness of the bore and concentricity of the bore to the outside surface of the barrel. More recently, various composite materials also have been used to form firearm barrels, such as for shotguns, but typically have required a metal liner along their inner wall for protection, thus adding to their cost in terms of both materials and manufacturing.
Accordingly, it can be seen that a need exists for a method and system for forming barrel assemblies for firearms that addresses the foregoing and other related and unrelated problems in the art.